Global fossil resources are going to be exhausted, and the environmental pollution is increasingly severe. Solving the problems of the resources and environment is the important task for the economic sustainable development in 21st century. However, the chemical fibers with petroleum as the starting material comprise about 67% in the total amount of the textile industry in China, the yield of which is over 50% in the world. It will be faced a severe problem in ensuring the petroleum supply in a long term and steadily. It has been an international trend to change the present situation that the petroleum resources are deeply relied on by the chemical fiber industry in China or even the world, and develop the utilization of the natural fibers. 2009 has been designated as the “International Year of Natural Fibers”. The usage of natural fibers has increased by 8% and 15% every year in the world and China, respectively. The yield of cotton, the main natural fibers in China, is about 6 million tons per year with a gap of about 6 to 8 million tons that is not likely to be compensated by planting cotton in the cereals cropland instead. The productivity has reached the plateau for other natural fibers in China, such as silk and wool, both of which have a yield of 100,000 tons per year. The bast fiber crops are cultivated in extensive conditions and suitable to be planted in various places, and have a great potential to be developed in the industrial scale. The most advantageous bast fiber crop is ramie. From of old, ramie is the typical crop mainly used in textile in China and known as “China grass” overseas. China has 90% of the ramie yield in the world and extremely high international competitive capacity that 80% of the ramie products are outputted to comprise over 60% of the global textile trade volume. There are 459 relatively large ramie textile and/or ramie textile manufacturing enterprises in China, offering nearly 1 million jobs.
The ramie industry is the traditional national industry in China and belongs to the labour intensive industries. In China, the employees in the ramie industry chain are up to several millions. The ramie dress has the advantages such as being stiff and neat, elegant, light, cool, breathable and anti-bacterial, and belongs to top grade consumer goods. The utilization of ramie fiber resources is turning from the traditional textile field to the biomass energy sources and biomaterials. Both the ramie materials and the ramie products have a broad market prospect.
The degumming of the ramie is an important step in the ramie processing. At present in China, most of the ramie processing enterprises adopt the chemical degumming, involving acid immersing, alkali boiling, and hammering-and-washing steps, which not only renders the degumming process long, the process steps complicated, the energy and water consumption high, and the pollution severe, but also causes damage to the ramie fibers and lowers the fiber quality. The biological degumming is focused in the clean production technology studies of the phloem fibers of the bast fiber crops at home and abroad, and is by the mechanism that the microorganisms and their secreted extracellular enzyme(s) are utilized to allow a series of reactions occur in relatively mild conditions so as to degrade the ramie phloem gum and release the fibers. The biological degumming is believed to be most possibly used in production practice in place of chemical degumming due to the avoidance of strong acids and alkalis, saving energy and water and little environmental pollution. The biological degumming of the ramie has been studied for over 80 years in China. Mainly, the superior degumming bacteria are screened from the nature and incubated into high-efficient degumming strains by physical or chemical mutagenesis, and then, the scaled-up bacterium-and-enzyme mixed liquor or the critical degumming enzyme(s) isolated therefrom is used for degumming. In the past decades, a number of degumming bacteria have been obtained from the microorganism resources, wherein the Erwinia carotovora strain T85-260 screened by the Institute of Bast Fiber Crops, Chinese Academy of Agricutral Sciences, the Bacillus alcalophilus strain screened by Wuhan University, the Bacillus alcalophilus strain screened by Shandong University, and the wild Bacillus cereus strain screened by Qingdao Continent Biotech Co., Ltd have ever been proceeded to the production test stage, and the others are still in the laboratory stage.
In the last 90s, the commercial production test has been performed for the biological degumming technologies. The patent “A technology for degumming the ramie jointly by bacteria and chemistry” (CN85103481) has been extended in 5 enterprises, and the patent “A process and equipment for biologically degumming the ramie” (CN95112564.8) has been tested for production in 6 enterprises including the Number 2 and 3 Ramie Textile Factories of Ruanjiang City, Hunan Province. The attempts failed mainly because the seed production technology is difficult to be mastered and the degumming capacity is not sufficient. The patent CN01106884.2 has been tested in Number 2 Ramie Textile Factory of Ruanjiang City, and the patent CN97109044.0 has been tested for production in Jiangxi Enda Hometextile Co., Ltd. These tests were in the joint manner of biological-and-chemical degumming. The large-scale production test of purely biological degumming was started in 2007 in the Star Textile Factory of Ruanjiang, Hunan. However, it has now been forced to change to joint biological-and-chemical degumming, which is mainly because the degummed ramie by purely biological degumming is not ideal and the products produced using the same are not welcome in the market.